Transmission system for hybrid vehicle and method for executing same

Abstract

The invention relates to a drivetrain for a hybrid vehicle and a method of executing the same. The transmission system comprises an internal combustion engine power system, a gearbox, a P3 motor and a differential mechanism. The gearbox is in transmission connection with the internal combustion engine power system through an internal combustion engine input shaft. The gearbox comprises a plurality of gear trains with different transmission ratios, and each gear train is connected or disconnected with an output shaft of the internal combustion engine in a one-way transmission mode through a corresponding switchable one-way clutch. Wherein the switchable one-way clutch has a disconnected state and a connected state; in the connected state, the switchable one-way clutch can transmit torque in a one-way mode. The gearbox and the P3 motor are connected to the differential mechanism in parallel through an internal combustion engine output shaft and a motor output shaft respectively. By the adoption of the transmission system, the speed regulation range is wide, the rotating speed of the engine and the rotating speed of the motor are easy to control, the time needed for switching to the target gear is short, and the success rate is high.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle transmission, and in particular to a transmission system for a hybrid vehicle and an implementation method thereof. Background Art

[0002] Currently, in hybrid vehicles, when the internal combustion engine and electric motor operate in parallel mode, the internal combustion engine must output torque directly to the wheels through the transmission. To achieve a wider operating speed range for the internal combustion engine, the transmission requires multiple gear ratios. Current hybrid vehicle transmission systems feature a multi-plate clutch or dog clutch between the internal combustion engine and transmission to connect and disconnect the transmission and internal combustion engine. The transmission also features synchronizers for shifting gears between the multiple gear sets.

[0003] A multi-plate clutch requires hydraulic control, making the transmission more complex and costly. A dog clutch requires speed regulation during clutch engagement to reduce noise and shock. This speed regulation increases transmission response time and makes vehicle speed control more difficult for the electric motor and internal combustion engine.

[0004] In addition, during the gear shifting process, the teeth of the dog clutch may be top-toothed, resulting in engagement failure, and the gear shifting process needs to be repeated to shift again, which increases the gear shifting duration of the transmission system and thus makes the control logic more complicated.

[0005] If a sequential shift system (such as a shift drum) is used to drive the shift forks and synchronizers of a three-speed transmission, it is not possible to jump directly from first gear to third gear. Instead, it is necessary to first adjust the speed from first gear and shift to second gear, and then adjust the speed from second gear and shift to third gear, which takes a long time to shift. Summary of the Invention

[0006] In order to solve the above technical problems, the present invention provides a transmission system for a hybrid vehicle and an execution method thereof.

[0007] According to an embodiment of the present invention, a transmission system for a hybrid vehicle is provided, comprising: an internal combustion engine power system, a gearbox, a P3 motor, and a differential. The gearbox is connected to the internal combustion engine power system via an internal combustion engine input shaft. The gearbox includes multiple gear trains with different transmission ratios, each of which can be connected or disconnected to the internal combustion engine output shaft in a one-way transmission manner via a corresponding switchable one-way clutch; wherein the switchable one-way clutch has a disconnected state and a connected state; in the connected state, the switchable one-way clutch can transmit torque in a one-way direction. The gearbox and the P3 motor are connected in parallel to the differential via the internal combustion engine output shaft and the motor output shaft, respectively.

[0008] According to some optional embodiments of the present invention, the gear train includes a driving gear connected to the input shaft of the internal combustion engine and a driven gear for outputting torque, and the driven gear and the output shaft of the internal combustion engine can be connected or disconnected in a one-way transmission manner via the switchable one-way clutch. In the disconnected state, no torque is transmitted between the driven gear and the output shaft of the internal combustion engine; in the connected state, when the speed of the driven gear is lower than the speed of the output shaft of the internal combustion engine, no torque is transmitted between the driven gear and the output shaft of the internal combustion engine. When the speed of the driven gear is not lower than the original speed of the output shaft of the internal combustion engine, the driven gear transmits torque to the output shaft of the internal combustion engine via the switchable one-way clutch, and the output shaft of the internal combustion engine and the driven gear achieve synchronous rotation.

[0009] According to some optional embodiments of the present invention, the gearbox includes three gear trains with different transmission ratios: a first gear gear train, a first gear gear train and a third gear gear train, and the transmission ratios of the three gear trains with different transmission ratios increase sequentially.

[0010] According to some optional embodiments of the present invention, an internal combustion engine power system includes an internal combustion engine and a P1 motor, wherein the P1 motor is power-coupled to the internal combustion engine.

[0011] According to an embodiment of the present invention, a method for executing a transmission system is provided. The transmission system is a transmission system for a hybrid vehicle according to any one of the above embodiments. The method is used for shifting gears of the transmission system. The method comprises:

[0012] The internal combustion engine power system stops outputting power and reduces the speed of the internal combustion engine input shaft until the speed of the driven gear of the gear train is lower than the speed of the internal combustion engine output shaft;

[0013] Each switchable one-way clutch is maintained or switched to a disconnected state;

[0014] The switchable one-way clutch corresponding to the gear train of the target gear position is switched from a disconnected state to a connected state;

[0015] The internal combustion engine power system outputs power and increases the speed of the internal combustion engine input shaft to a speed at which the speed of the driven gear of the gear train is not less than the original speed of the internal combustion engine output shaft, and the gear train transmits torque to the internal combustion engine output shaft through the switchable one-way clutch, and enables the internal combustion engine output shaft and the driven gear to achieve synchronous rotation; and

[0016] Torque is delivered through the differential.

[0017] According to some optional embodiments of the present invention, the gear shift of the transmission system is: the transmission system switches from a series mode of the internal combustion engine power system and the P3 motor to a parallel mode, and the execution method includes:

[0018] The internal combustion engine power system stops outputting power and reduces the speed of the internal combustion engine input shaft until the speed of the driven gear of the gear train is lower than the speed of the internal combustion engine output shaft;

[0019] The switchable one-way clutch corresponding to the target gear train is switched to a connected state;

[0020] The internal combustion engine power system outputs power and increases the speed of the internal combustion engine input shaft to a speed at which the speed of the driven gear of the gear train is not less than the original speed of the internal combustion engine output shaft, and the gear train transmits torque to the internal combustion engine output shaft through the switchable one-way clutch, and enables the internal combustion engine output shaft and the driven gear to achieve synchronous rotation; and

[0021] Torque is delivered through the differential.

[0022] According to some optional embodiments of the present invention, the gear switching of the transmission system is: the transmission system switches from a relatively low gear to a relatively high gear, and the execution method includes:

[0023] The internal combustion engine power system stops outputting power and reduces the speed of the internal combustion engine input shaft to a point where the speed of the driven gear of the gear train in the lower gear ratio is lower than the speed of the internal combustion engine output shaft;

[0024] The switchable one-way clutch corresponding to the gear train of the relatively low gear is switched from the connected state to the disconnected state;

[0025] The switchable one-way clutch corresponding to the gear train of the higher transmission gear is switched from the disconnected state to the connected state;

[0026] The internal combustion engine power system outputs power and increases the speed of the internal combustion engine input shaft to a speed at which the speed of the driven gear of the gear train with a relatively high transmission gear is not lower than the original speed of the internal combustion engine output shaft, and the gear train with a relatively high transmission gear transmits torque to the internal combustion engine output shaft through the switchable one-way clutch, and causes the internal combustion engine output shaft and the driven gear to rotate synchronously; and

[0027] Torque is delivered through the differential.

[0028] According to some optional embodiments of the present invention, the gearbox includes three gear trains with different transmission ratios: a first-gear gear train, a second-gear gear train, and a third-gear gear train, and the transmission ratios of the three gear trains with different transmission ratios increase in sequence;

[0029] The gear switching of the transmission system is: the transmission system switches from the first gear to the third gear, and the execution method includes:

[0030] The internal combustion engine power system stops outputting power and reduces the speed of the internal combustion engine input shaft until the speed of the driven gear of the first gear train is lower than the speed of the internal combustion engine output shaft;

[0031] The first switchable one-way clutch corresponding to the first gear train is switched from a connected state to a disconnected state;

[0032] The second switchable one-way clutch corresponding to the second gear train is switched from a disconnected state to a connected state;

[0033] The second switchable one-way clutch corresponding to the second gear train is switched from a connected state to a disconnected state;

[0034] The third switchable one-way clutch corresponding to the third gear train is switched from a disconnected state to a connected state;

[0035] The internal combustion engine power system outputs power and increases the speed of the internal combustion engine input shaft to a speed at which the speed of the driven gear of the third gear train is not lower than the original speed of the internal combustion engine output shaft, the third gear train transmits torque to the internal combustion engine output shaft through the third switchable one-way clutch, and the internal combustion engine output shaft and the driven gear of the third gear train rotate synchronously; and

[0036] Torque is delivered through the differential.

[0037] According to some optional embodiments of the present invention, the gear switching of the transmission system is: the transmission system switches from a relatively high gear to a relatively low gear, and the execution method includes:

[0038] The internal combustion engine power system stops outputting power and reduces the speed of the internal combustion engine input shaft until the speed of the driven gear of the gear train at the higher gear ratio is lower than the speed of the internal combustion engine output shaft;

[0039] The switchable one-way clutch corresponding to the gear train of the relatively high transmission gear is switched from the connected state to the disconnected state;

[0040] reducing the speed of the input shaft of the internal combustion engine until the speed of the driven gear of the gear train in the lower gear of the transmission ratio is lower than the speed of the output shaft of the internal combustion engine;

[0041] The switchable one-way clutch corresponding to the gear train of the relatively low gear position is switched from a disconnected state to a connected state;

[0042] The internal combustion engine power system outputs power and increases the speed of the internal combustion engine input shaft to a speed at which the speed of the driven gear of the gear train in the relatively low gear ratio is not lower than the original speed of the internal combustion engine output shaft, and the gear train in the relatively low gear ratio transmits torque to the internal combustion engine output shaft through the switchable one-way clutch, so that the internal combustion engine output shaft and the driven gear achieve synchronous rotation; and

[0043] Torque is delivered through the differential.

[0044] According to some optional embodiments of the present invention, the gear switching of the transmission system is: the transmission system switches from a parallel mode of the internal combustion engine power system and the P3 motor to a series mode, and the execution method further includes:

[0045] The internal combustion engine power system stops outputting power and reduces the speed of the internal combustion engine input shaft until the speed of the driven gear of the gear train is lower than the speed of the internal combustion engine output shaft;

[0046] Each switchable one-way clutch is maintained in or switched to a disconnected state.

[0047] In the transmission system and method for hybrid vehicles according to the present invention, compared to conventional transmission systems, the clutch between the internal combustion engine and the transmission is eliminated. Instead, each gear train in the transmission has a corresponding switchable one-way clutch. The switchable one-way clutch has a disconnected state and a connected state. In the connected state, the switchable one-way clutch can transmit torque in one direction. This transmission system structure provides a wide speed range for the internal combustion engine and the P1 motor. During the switching between the connected and disconnected states, the outer ring speed of the switchable one-way clutch corresponding to the target gear train only needs to be lower than the inner ring speed. That is, the internal combustion engine input shaft is decelerated to a speed at which the driven gear of the target gear train rotates less than the speed of the internal combustion engine output shaft. This ensures a high shift success rate and eliminates the need for retrying the shift process. Furthermore, for a sequential shifting system, skipping between first and third gears, as well as higher gears, is also possible without waiting for the intermediate gears to synchronize their speeds. Consequently, the transmission system according to the present invention achieves a short shift time and a high success rate when shifting to the target gear. Moreover, since there is no gear matching between the active and driven parts of the switchable one-way clutch, the entire power drive system can be switched with a high success rate, low noise and low impact, thereby extending the service life of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0049] Figure 1 A schematic structural diagram of a transmission system according to an embodiment of the present invention is shown; and

[0050] Figure 2 A flow chart showing an execution method of a transmission system according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0052] In the description of this application, unless otherwise specified, the terms "upper," "lower," "inner," "outer," etc., indicating directions or positional relationships, are intended only to facilitate the description of this application and simplify the description, and are not intended to indicate or imply that the devices or components referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The directional terms appearing in the following description refer to the directions shown in the drawings and are not intended to limit the specific structure of this application.

[0053] In the following description of the present invention, it should be noted that, unless otherwise specified, "plurality" means more than two. Terms such as "inside" and "outside" indicating orientations or positional relationships are intended solely to facilitate and simplify the description of the present invention and do not indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. The directional terms used in the following description refer to directions shown in the drawings and do not limit the specific structure of the present invention.

[0054] In the description of the present invention, it should also be noted that, unless otherwise expressly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium. In addition, it should be understood that the term "torque-resistant connection" refers to the connection between two elements in a manner that does not rotate relative to each other, so that torque can be transmitted between the two elements, and the torque-resistant connection can be achieved through interference fit, bolt connection, gear connection, welding, spline connection, adhesive bonding, etc., or by forming the two mentioned elements into one piece. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0055] The present invention relates to a transmission system for a hybrid vehicle. The transmission system comprises an electric motor power system and an internal combustion engine power system, which are connected in parallel to a differential to transmit torque to the wheels and provide power. The transmission system can switch between a series mode and a parallel mode in which the internal combustion engine power system and the electric motor power system are connected. In the parallel mode, the transmission system can switch between gears with different transmission ratios in the internal combustion engine power system. The system has the advantages of short switching time, fast response speed, and high success rate.

[0056] Figure 1 FIG2 shows a schematic structural diagram of a transmission system according to an embodiment of the present invention. Figure 1 As shown, the transmission system includes: an internal combustion engine power system 100, a gearbox 200, a P3 motor 300 and a differential 400.

[0057] The internal combustion engine power system 100 may include an internal combustion engine 1 and a P1 motor 2. The internal combustion engine 1 and the P1 motor 2 are coupled to the internal combustion engine 1 via gears. The P1 motor 2 can assist the internal combustion engine 1 in providing power. Torque can be transmitted between the internal combustion engine power system 100 and the transmission 200 via the internal combustion engine input shaft 3. The transmission 200 and the P3 motor 300 are connected in parallel to the differential 400 via the internal combustion engine output shaft 7 and the motor output shaft 8, respectively.

[0058] The gearbox 200 includes a plurality of gear components with different gears. Figure 1 As shown, in some embodiments, the gearbox 200 includes three gear assemblies with different gears: a first gear assembly 4, a second gear assembly 5, and a third gear assembly 6. It should be understood that the number of the above gear assemblies is only exemplary, and other numbers of gear assemblies can also be provided. Each gear assembly includes a gear train with different transmission ratios and a corresponding switchable one-way clutch. Figure 1As shown, in some embodiments, the first gear assembly 4 has a first gear train 41 with the smallest gear ratio and a corresponding first switchable one-way clutch 42; the second gear assembly 5 has a second gear train 51 with a slightly larger gear ratio and a corresponding second switchable one-way clutch 52; and the third gear assembly 6 has a third gear train 61 with the largest gear ratio and a corresponding third switchable one-way clutch 62. Each gear train can be connected or disconnected to the internal combustion engine output shaft 7 in a one-way transmission manner via a corresponding switchable one-way clutch. The switchable one-way clutch has a disconnected state and a connected state. In the connected state, the switchable one-way clutch can transmit torque in one direction, that is, torque can only be transmitted in one direction from the gear train to the internal combustion engine output shaft 7, and cannot transmit torque in the opposite direction.

[0059] Specifically, the gear train includes a mutually meshing driving gear and a driven gear. The driving gear is torsionally connected to the internal combustion engine input shaft 3, and the driven gear is torsionally connected to the outer ring of the switchable one-way clutch. That is, the torque output by the internal combustion engine power system 100 can be transmitted to the outer ring of the switchable one-way clutch. The inner ring of the switchable one-way clutch is torsionally connected to the internal combustion engine output shaft 7.

[0060] In the disconnected state, the outer ring and the inner ring of the switchable one-way clutch are disconnected, and no torque is transmitted between them, that is, no torque is transmitted between the driven gears connected to them and the internal combustion engine output shaft 7.

[0061] In the connected state, when the speed of the outer ring of the switchable one-way clutch is lower than the speed of the inner ring, that is, the speed of the driven gear is lower than the speed of the internal combustion engine output shaft 7, the switchable one-way clutch is similar to a general one-way clutch. At this time, the outer ring and the inner ring can rotate freely, so the outer ring cannot transmit torque to the inner ring, and the gear system of the corresponding gear cannot transmit torque to the internal combustion engine output shaft 7.

[0062] In the connected state, when the rotation speed of the outer ring of the switchable one-way clutch is lower than the rotation speed of the inner ring, that is, the rotation speed of the driven gear is not lower than the original rotation speed of the internal combustion engine output shaft 7, the outer ring and the inner ring are clamped. At this time, the outer ring transmits torque to the inner ring, that is, the driven gear transmits torque to the internal combustion engine output shaft 7 through the switchable one-way clutch, and the rotation speeds of the outer ring and the inner ring are gradually synchronized, so the internal combustion engine output shaft 7 rotates synchronously with the driven gear.

[0063] The present invention further provides a hybrid vehicle, comprising a transmission system as described in any of the above embodiments, and a wheel 500. The transmission system's differential 400 is torque-transmittingly connected to the wheel 500. When any of the multiple shift assemblies is in a connected state, and the outer and inner rings of the switchable one-way clutch rotate synchronously to transmit torque, the power provided by the internal combustion engine power system 100 can be connected in parallel with the P3 motor 300, thereby outputting power to the wheel 500.

[0064] The present invention further provides an execution method for a transmission system, wherein the transmission system is the transmission system for a hybrid vehicle described in any one of the above embodiments, and the execution method is used for gear switching of the transmission system.

[0065] Figure 2 FIG. 1 is a flow chart showing an execution method of a transmission system according to an embodiment of the present invention. Figure 2 As shown, the execution method includes:

[0066] S1: The internal combustion engine power system 100 stops outputting power and reduces the speed of the internal combustion engine input shaft 3 until the speed of the driven gear of the gear train is lower than the speed of the internal combustion engine output shaft 7;

[0067] S2: Each switchable one-way clutch is maintained or switched to the disconnected state;

[0068] S3: The switchable one-way clutch corresponding to the target gear train switches from the disconnected state to the connected state;

[0069] S4: The internal combustion engine power system 100 outputs power and increases the speed of the internal combustion engine input shaft 3 to a speed at which the speed of the driven gear of the gear train is not lower than the original speed of the internal combustion engine output shaft 7. The gear train transmits torque to the internal combustion engine output shaft 7 through the switchable one-way clutch, and the internal combustion engine output shaft 7 and the driven gear achieve synchronous rotation.

[0070] S5: Torque is output through the differential 400 .

[0071] It should be understood that when the above-mentioned switchable one-way clutch is in the switching state, the rotational speed of the outer ring of the switchable one-way clutch should be less than the rotational speed of the inner ring, that is, the rotational speed of the driven gear of the gear system is less than the rotational speed of the internal combustion engine output shaft 7. At this time, the switchable one-way clutch does not transmit torque in the connected state, so the switchable one-way clutch can switch states safely and smoothly.

[0072] In some embodiments, the gear switching of the transmission system may include, but is not limited to: switching the transmission system from a series mode to a parallel mode between the internal combustion engine power system 100 and the P3 motor 300, switching the transmission system from a relatively low gear to a relatively high gear, switching the transmission system from a first gear to a third gear, switching the transmission system from a relatively high gear to a relatively low gear, and switching the transmission system from a parallel mode to a series mode between the internal combustion engine power system 100 and the P3 motor 300. The execution methods of the transmission system in the above-mentioned situations are described below.

[0073] In some embodiments, the gear shift of the transmission system is: the transmission system switches from a series mode of the internal combustion engine power system 100 and the P3 motor 300 to a parallel mode, and the execution method includes:

[0074] The internal combustion engine power system 100 stops outputting power and reduces the speed of the internal combustion engine input shaft 3 until the speed of the driven gear of the gear train is lower than the speed of the internal combustion engine output shaft 7;

[0075] The switchable one-way clutch corresponding to the target gear train is switched to a connected state;

[0076] The internal combustion engine power system 100 outputs power and increases the speed of the internal combustion engine input shaft 3 to a speed at which the speed of the driven gear of the gear train is not lower than the original speed of the internal combustion engine output shaft 7. The gear train transmits torque to the internal combustion engine output shaft 7 through the switchable one-way clutch, and causes the internal combustion engine output shaft 7 and the driven gear to rotate synchronously; and

[0077] The torque is output through the differential 400 .

[0078] In the above case, since the initial state is the series mode of the internal combustion engine power system 100 and the P3 motor 300, each switchable one-way clutch is already in a disconnected state, so step S2 has actually been achieved, so there is no need to specifically execute step S2.

[0079] Furthermore, the target gear train shown can be, but is not limited to, the first gear train 41. In a sequential gear sequence, if the current gear is between the first gear assembly 4 and the second gear assembly 5, the target gear train shown can be either the first gear train 41 or the second gear train 51. It will be appreciated that if the current gear is between the second gear assembly 5 and the third gear assembly 6, the target gear train shown can be either the second gear train 51 or the third gear train 61. Therefore, when the transmission system switches from a series mode to a parallel mode between the internal combustion engine power system 100 and the P3 motor 300, the gear after the switching step is completed can be selected based on actual conditions.

[0080] In some embodiments, the gear shift of the transmission system is: the transmission system is switched from a relatively low gear to a relatively high gear. Specifically, taking the transmission system switching from the first gear assembly 4 to the second gear assembly 5 as an example, the execution method includes:

[0081] The internal combustion engine power system 100 stops outputting power and reduces the speed of the internal combustion engine input shaft 3 until the speed of the driven gear of the first gear train 41 is lower than the speed of the internal combustion engine output shaft 7;

[0082] The first switchable one-way clutch 42 is switched from a connected state to a disconnected state;

[0083] The second switchable one-way clutch 52 is switched from a disconnected state to a connected state;

[0084] The internal combustion engine power system 100 outputs power and increases the speed of the internal combustion engine input shaft 3 to a point where the speed of the driven gear of the first-gear gear train 51 is not lower than the original speed of the internal combustion engine output shaft 7. The first-gear gear train 51 transmits torque to the internal combustion engine output shaft 7 through the second switchable one-way clutch 52, and the internal combustion engine output shaft 7 and the driven gear rotate synchronously.

[0085] The torque is output through the differential 400 .

[0086] Similarly, the case where the transmission system switches from the second gear assembly 5 to the third gear assembly 6 is similar to the above-mentioned execution method and will not be repeated here.

[0087] In some embodiments, the gear shift of the transmission system is: the transmission system is switched from the first gear to the third gear, and the execution method includes:

[0088] The internal combustion engine power system 100 stops outputting power and reduces the speed of the internal combustion engine input shaft 3 until the speed of the driven gear of the first gear train 41 is lower than the speed of the internal combustion engine output shaft 7;

[0089] The first switchable one-way clutch 42 corresponding to the first gear gear train 41 is switched from a connected state to a disconnected state;

[0090] The second switchable one-way clutch 52 corresponding to the second gear train 51 is switched from a disconnected state to a connected state;

[0091] The second switchable one-way clutch 52 corresponding to the second gear train 51 is switched from a connected state to a disconnected state;

[0092] The third switchable one-way clutch 62 corresponding to the third gear gear train 61 is switched from a disconnected state to a connected state;

[0093] The internal combustion engine power system 100 outputs power and increases the speed of the internal combustion engine input shaft 3 to a speed at which the speed of the driven gear of the third-gear gear train 61 is not lower than the original speed of the internal combustion engine output shaft 7. The third-gear gear train 61 transmits torque to the internal combustion engine output shaft 7 via the third switchable one-way clutch 62, and the internal combustion engine output shaft 7 and the driven gear of the third-gear gear train 61 rotate synchronously.

[0094] The torque is output through the differential 400 .

[0095] It should be understood that in the above situation, since the sequential gear cannot be switched directly from the first gear to the third gear but instead passes through the second gear, additional steps are added between step S2 and step S3: the second switchable one-way clutch 52 corresponding to the second gear gear train 51 is switched from a disconnected state to a connected state; and the second switchable one-way clutch 52 corresponding to the second gear gear train 51 is switched from a connected state to a disconnected state. However, according to the execution method of the present invention, during the process of switching from the first gear to the third gear, the second switchable one-way clutch 52 is switched from a disconnected state to a connected state and can be immediately switched back to a disconnected state. The gear switching only passes through the second gear, without having to wait for the driven gear of the second gear gear train 51 to synchronize with the speed of the internal combustion engine output shaft 7, thereby significantly reducing the time for skipping gears.

[0096] In addition, in an embodiment with more gears, it is also possible to switch gears between other gears. The method and steps are similar to the above steps and will not be repeated here.

[0097] In some embodiments, the gear shift of the transmission system is: the transmission system is switched from a relatively high gear to a relatively low gear. Specifically, taking the transmission system switching from the second gear assembly 5 to the first gear assembly 4 as an example, the execution method includes:

[0098] The internal combustion engine power system 100 stops outputting power and reduces the speed of the internal combustion engine input shaft 3 until the speed of the driven gear of the second gear train 51 is lower than the speed of the internal combustion engine output shaft 7;

[0099] The second switchable one-way clutch 52 corresponding to the second gear train 51 is switched from a connected state to a disconnected state;

[0100] reducing the speed of the internal combustion engine input shaft 3 until the speed of the driven gear of the first gear train 41 is lower than the speed of the internal combustion engine output shaft 7;

[0101] The first switchable one-way clutch 42 corresponding to the first gear gear train 41 is switched from a disconnected state to a connected state;

[0102] The internal combustion engine power system 100 outputs power and increases the speed of the internal combustion engine input shaft 3 to a point where the speed of the driven gear of the first gear train 41 is not lower than the original speed of the internal combustion engine output shaft 7. The first gear train 41 transmits torque to the internal combustion engine output shaft 7 through the first switchable one-way clutch 42, and the internal combustion engine output shaft 7 and the driven gear rotate synchronously.

[0103] The torque is output through the differential 400 .

[0104] It is understood that when the speed of the driven gear of the first-gear gear train 41 is lower than the speed of the internal combustion engine output shaft 7, the speed of the driven gear of the second-gear gear train 51 is necessarily lower than the speed of the internal combustion engine output shaft 7. This means that the second switchable one-way clutch 52 no longer transmits torque, satisfying the conditions for switching the second switchable one-way clutch 52 from a connected state to a disconnected state. Therefore, the order of the step of "switching the second switchable one-way clutch 52 corresponding to the second-gear gear train 51 from a connected state to a disconnected state" and the step of "reducing the speed of the internal combustion engine input shaft 3 to a point where the speed of the driven gear of the first-gear gear train 41 is lower than the speed of the internal combustion engine output shaft 7" can be reversed.

[0105] In some embodiments, the gear switching of the transmission system is: the transmission system switches from a parallel mode of the internal combustion engine power system 100 and the P3 motor 300 to a series mode, and the execution method further includes:

[0106] The internal combustion engine power system 100 stops outputting power and reduces the speed of the internal combustion engine input shaft 3 until the speed of the driven gear of the gear train is lower than the speed of the internal combustion engine output shaft 7;

[0107] Each switchable one-way clutch is maintained in or switched to a disconnected state.

[0108] That is, when all the switchable one-way clutches are in the disengaged state, the transmission system is in the series mode.

[0109] In the transmission system and method for hybrid vehicles according to the present invention, compared to conventional transmission systems, the clutch between the internal combustion engine and the transmission is eliminated. Instead, each gear train in the transmission has a corresponding switchable one-way clutch. The switchable one-way clutch has a disconnected state and a connected state. In the connected state, the switchable one-way clutch can transmit torque in one direction. This transmission system structure provides a wide speed range for the internal combustion engine and the P1 motor. During the switching between the connected and disconnected states, the outer ring speed of the switchable one-way clutch corresponding to the target gear train only needs to be lower than the inner ring speed. That is, the internal combustion engine input shaft is decelerated to a speed at which the driven gear of the target gear train rotates less than the speed of the internal combustion engine output shaft. This ensures a high shift success rate and eliminates the need for retrying the shift process. Furthermore, for a sequential shifting system, skipping between first and third gears, as well as higher gears, is also possible without waiting for the intermediate gears to synchronize their speeds. Consequently, the transmission system according to the present invention achieves a short shift time and a high success rate when shifting to the target gear. Moreover, since there is no gear matching between the active and driven parts of the switchable one-way clutch, the entire power drive system can be switched with a high success rate, low noise and low impact, thereby extending the service life of the vehicle.

[0110] While the foregoing descriptions illustrate possible embodiments, it should be understood that numerous variations exist through combinations of all known and other technical features and implementations readily conceivable to a skilled artisan. Furthermore, it should be understood that the exemplary embodiments serve merely as examples and in no way limit the scope, application, or configuration of the present invention. The foregoing descriptions are intended primarily to provide a skilled artisan with technical guidance for implementing at least one exemplary embodiment. Various modifications, particularly regarding the functionality and structure of the components described, may be made without departing from the scope of the claims.

Claims

1. A transmission system for a hybrid vehicle, characterized in that: include: Internal combustion engine power system (100); A gearbox (200) is connected to the internal combustion engine power system (100) via an internal combustion engine input shaft (3); the gearbox (200) includes a plurality of gear trains with different transmission ratios, each gear train being connected or disconnected to the internal combustion engine output shaft (7) in a one-way transmission manner via a corresponding switchable one-way clutch; wherein the switchable one-way clutch has a disconnected state and a connected state; in the connected state, the switchable one-way clutch is capable of transmitting torque in one direction; P3 motor (300); and A differential (400), wherein the gearbox (200) and the P3 motor (300) are connected in parallel to the differential (400) via an internal combustion engine output shaft (7) and a motor output shaft (8), respectively.

2. The transmission system according to claim 1, wherein: The gear train comprises a driving gear connected to the internal combustion engine input shaft (3) and a driven gear for outputting torque, wherein the driven gear and the internal combustion engine output shaft (7) can be connected or disconnected in a one-way transmission manner via the switchable one-way clutch; In the disconnected state, no torque is transmitted between the driven gear and the internal combustion engine output shaft (7); In the connected state, when the rotational speed of the driven gear is lower than the rotational speed of the internal combustion engine output shaft (7), no torque is transmitted between the driven gear and the internal combustion engine output shaft (7); when the rotational speed of the driven gear is not lower than the original rotational speed of the internal combustion engine output shaft (7), the driven gear transmits torque to the internal combustion engine output shaft (7) through the switchable one-way clutch, and the internal combustion engine output shaft (7) and the driven gear achieve synchronous rotation.

3. The transmission system according to claim 1, wherein: The gearbox (200) comprises three gear trains with different transmission ratios: a first gear train (41), a second gear train (51) and a third gear train (61), wherein the transmission ratios of the three gear trains with different transmission ratios increase in sequence.

4. The transmission system according to claim 1, wherein: An internal combustion engine power system (100) comprises an internal combustion engine (1) and a P1 motor (2), wherein the P1 motor (2) is power-coupled to the internal combustion engine (1).

5. A method for executing a transmission system, wherein the transmission system is a transmission system for a hybrid vehicle according to any one of claims 1 to 4, and the method is used for shifting gears of the transmission system; the method comprising: The internal combustion engine power system (100) stops outputting power and reduces the speed of the internal combustion engine input shaft (3) until the speed of the driven gear of the gear train is lower than the speed of the internal combustion engine output shaft (7); Each switchable one-way clutch is maintained or switched to a disconnected state; The switchable one-way clutch corresponding to the gear train of the target gear position is switched from a disconnected state to a connected state; The internal combustion engine power system (100) outputs power and increases the speed of the internal combustion engine input shaft (3) to a speed of the driven gear of the gear train that is not lower than the original speed of the internal combustion engine output shaft (7), and the gear train transmits torque to the internal combustion engine output shaft (7) through the switchable one-way clutch, and enables the internal combustion engine output shaft (7) and the driven gear to achieve synchronous rotation; and The torque is output through the differential (400).

6. The execution method according to claim 5, wherein: The gear switching of the transmission system is as follows: the transmission system switches from a series mode of the internal combustion engine power system (100) and the P3 motor (300) to a parallel mode, and the execution method includes: The internal combustion engine power system (100) stops outputting power and reduces the speed of the internal combustion engine input shaft (3) until the speed of the driven gear of the gear train is lower than the speed of the internal combustion engine output shaft (7); The switchable one-way clutch corresponding to the target gear train is switched to a connected state; The internal combustion engine power system (100) outputs power and increases the speed of the internal combustion engine input shaft (3) to a speed of the driven gear of the gear train that is not lower than the original speed of the internal combustion engine output shaft (7), and the gear train transmits torque to the internal combustion engine output shaft (7) through the switchable one-way clutch, and enables the internal combustion engine output shaft (7) and the driven gear to achieve synchronous rotation; and The torque is output through the differential (400).

7. The execution method according to claim 5, wherein: The gear shift of the transmission system is: the transmission system is switched from a relatively low gear to a relatively high gear, and the execution method includes: The internal combustion engine power system (100) stops outputting power and reduces the speed of the internal combustion engine input shaft (3) until the speed of the driven gear of the gear train in the lower gear ratio is lower than the speed of the internal combustion engine output shaft (7); The switchable one-way clutch corresponding to the gear train of the relatively low gear is switched from the connected state to the disconnected state; The switchable one-way clutch corresponding to the gear train of the higher transmission gear is switched from the disconnected state to the connected state; The internal combustion engine power system (100) outputs power and increases the speed of the internal combustion engine input shaft (3) to a speed at which the speed of the driven gear of the gear train with a relatively high transmission gear position is not lower than the original speed of the internal combustion engine output shaft (7), the gear train with a relatively high transmission gear position transmits torque to the internal combustion engine output shaft (7) through the switchable one-way clutch, and enables the internal combustion engine output shaft (7) and the driven gear to achieve synchronous rotation; and The torque is output through the differential (400).

8. The execution method according to claim 7, wherein: The gearbox (200) includes three gear trains with different transmission ratios: a first gear train (41), a second gear train (51), and a third gear train (61), wherein the transmission ratios of the three gear trains with different transmission ratios increase in sequence; The gear switching of the transmission system is: the transmission system switches from the first gear to the third gear, and the execution method includes: The internal combustion engine power system (100) stops outputting power and reduces the speed of the internal combustion engine input shaft (3) until the speed of the driven gear of the first gear train (41) is lower than the speed of the internal combustion engine output shaft (7); The first switchable one-way clutch (42) corresponding to the first gear train (41) is switched from a connected state to a disconnected state; The second switchable one-way clutch (52) corresponding to the second gear train (51) is switched from a disconnected state to a connected state; The second switchable one-way clutch (52) corresponding to the second gear train (51) is switched from a connected state to a disconnected state; The third switchable one-way clutch (62) corresponding to the third gear train (61) is switched from a disconnected state to a connected state; The internal combustion engine power system (100) outputs power and increases the speed of the internal combustion engine input shaft (3) to a speed at which the speed of the driven gear of the third gear train (61) is not lower than the original speed of the internal combustion engine output shaft (7), the third gear train (61) transmits torque to the internal combustion engine output shaft (7) through a third switchable one-way clutch (62), and enables the internal combustion engine output shaft (7) and the driven gear of the third gear train (61) to achieve synchronous rotation; and The torque is output through the differential (400).

9. The execution method according to claim 5, wherein: The gear shift of the transmission system is: the transmission system switches from a relatively high gear to a relatively low gear, and the execution method includes: The internal combustion engine power system (100) stops outputting power and reduces the rotational speed of the internal combustion engine input shaft (3) until the rotational speed of the driven gear of the gear train at the higher gear ratio is lower than the rotational speed of the internal combustion engine output shaft (7); The switchable one-way clutch corresponding to the gear train of the relatively high transmission gear is switched from the connected state to the disconnected state; reducing the rotational speed of the internal combustion engine input shaft (3) until the rotational speed of the driven gear of the gear train at the lower gear of the transmission ratio is lower than the rotational speed of the internal combustion engine output shaft (7); The switchable one-way clutch corresponding to the gear train of the relatively low gear position is switched from a disconnected state to a connected state; The internal combustion engine power system (100) outputs power and increases the speed of the internal combustion engine input shaft (3) to a speed at which the speed of the driven gear of the gear train with a relatively low transmission gear ratio is not lower than the original speed of the internal combustion engine output shaft (7), the gear train with a relatively low transmission gear ratio transmits torque to the internal combustion engine output shaft (7) through the switchable one-way clutch, and enables the internal combustion engine output shaft (7) and the driven gear to achieve synchronous rotation; and The torque is output through the differential (400).

10. The execution method according to claim 5, wherein: The gear switching of the transmission system is as follows: the transmission system switches from a parallel mode of the internal combustion engine power system (100) and the P3 motor (300) to a series mode, and the execution method further includes: The internal combustion engine power system (100) stops outputting power and reduces the speed of the internal combustion engine input shaft (3) until the speed of the driven gear of the gear train is lower than the speed of the internal combustion engine output shaft (7); Each switchable one-way clutch is maintained in or switched to a disconnected state.

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